Helmet cover



FIG. 1 is a front perspective view of a helmet cover showing our new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a front elevation view thereof;

FIG. 4 is a left side elevation view thereof;

FIG. 5 is a rear elevation view thereof; and,

FIG. 6 is a bottom plan thereof. 

CLAIM The ornamental design for a helmet cover, as shown and described. 